Not Applicable.
Not Applicable.
(1) Field of the Invention
The present invention relates to a detectable heavy duty needle cannula for use in hypodermic syringes and the like. The needle cannula comprises a magnetized stainless steel alloy, which enables the needle cannula to be detectable in metal detectors that are commonly used in the meat processing industry to detect broken needle cannulas in the flesh of slaughtered animals. The needle cannula further comprises a sidewall that is thicker than prior art needle cannulas. The thicker sidewall imparts to the needle cannula greater resistance to breakage during the process of injecting animal health products into an animal and greater detectability in a metal detector.
(2) Description of Related Art
Stainless steel alloys are extensively used in manufacturing needle cannulas for hypodermic syringes for injecting animal health products into animals. From time to time, when these needles are used to vaccinate an animal, particularly the large domestic animals used for meat production, a part of the needle cannula breaks off and remains lodged within the flesh of the animal. Because meat containing a broken piece of needle is unfit for human consumption, any meat that contains a broken needle must be separated from the meat that is safe for human consumption.
The meat processing industry uses metal detectors to detect broken needles lodged within the flesh of the animal. However, because the needle cannulas used for veterinary purposes are made from non-magnetic stainless steel alloys, they are difficult to detect with the metal detectors that are used in the meat processing industry. Detection is particularly difficult when the needle""s length to diameter ratio is low because at such low ratios the orientation of the needle in the meat affects detectability.
In order to improve detection of these needles, the metal detectors are routinely operated at high sensitivity levels. However, at sensitivity levels the frequency of false positives is increased. Therefore, a greater proportion of meat than is necessary is culled.
Therefore, there is a need for a needle cannula that is more resistant to breakage during the process of injecting animal health products into an animal. There is also a need for a needle cannula that can be readily detected in the metal detectors that are commonly used in the meat processing industry to detect broken needle cannula in the flesh of animals after slaughter.
The present invention provides a detectable heavy duty needle cannula for use in hypodermic syringes and the like. The needle cannula comprises a magnetic stainless steel alloy, which enables the needle cannula to be detectable in a metal detector. Particularly in the metal detectors that are commonly used in the meat processing industry to detect broken needle cannulas in the flesh of slaughtered animals. The needle cannula further comprises a sidewall that is thicker than prior art needle cannulas, which imparts to the needle cannula greater resistance to breakage during the process of injecting animal health products into an animal and increases its detectability in a metal detector.
The present invention provides a needle assembly comprising an elongate permanently magnetizable or magnetic stainless steel needle cannula having a proximal end, a distal end and a sidewall therebetween, the cannula having a lumen therethrough wherein the cannula at its proximal end is securely fixed to a mounting hub which is capable of being mounted on a device for injecting a dosage of a material in an animal. In particular, a needle assembly for use in a hypodermic needle and the device is a hypodermic syringe. Preferably, the sidewall has a thickness greater than 0.46 mm, in particular when the lumen has a diameter of about 1.19 mm. In a preferred embodiment, the needle cannula has a circular cross-section and the mounting hub includes projections extending therefrom for threaded engagement with a luer collar.
The present invention also provides a stainless steel-tubular needle defined by at least one wall forming the tube and supported on a hub for mounting on a device for injecting a dosage of a material in an animals, wherein the needle is magnetizable or magnetic to a level which enables detection of the magnetism of the needle when broken off in the flesh of an animal when the animal is slaughtered and processed. Preferably, the needle is a hypodermic needle and wherein the material is a fluid. It is further preferable that the wall have a thickness of greater than 0.018 inch and an inside diameter of about 0.046 inch. It is preferable further still that the needle have a circular cross-section.
The present invention also provides a method of injecting flesh of a living food animal which comprises (a) providing an injection means comprising a tubular needle defined by at least one wall forming the tube and supported on a hub and mounted on a device for injecting a dosage of a material in an animal, wherein the needle is made of stainless steel, which is magnetizable or magnetic at a level that enables detection of the magnetism of the needle if the needle is broken off in the flesh of the living animal during the injection; and (b) injecting the living animal with the dosage using the needle, whereby when the needle breaks in the animal during the injection, the needle can be detected in the flesh of the animal upon slaughter and processing into the food.
The present invention further provides in a slaughtering method for slaughter and processing of animals for food while conveying the flesh of the animal, the improvement which comprises detecting a broken stainless steel tubular needle in the flesh, wherein the needle has at least one wall and is supported on a hub for mounting on a device for injecting a dosage of a material into an animal, wherein the needle is magnetized to a level which enables detection of the magnetism of the needle when broken off in the flesh of an animal when the animal is slaughtered and processed. In the foregoing methods it is preferable that the needle be a hypodermic needle. Particularly, a needle wherein the wall has a thickness of greater than 0.018 inch, and further, wherein the needle has an inside diameter of about 0.046 inch. The method is particularly useful when the animal is a swine.
In either of the above methods, the needle can be the above permanently magnetizable or magnetic stainless steel needle cannula having a proximal end, a distal end and a sidewall therebetween, the cannula having a lumen therethrough defining a cannula longitudinal axis wherein the cannula at its proximal end is securely fixed to a mounting hub which is capable of being mounted on a device for injecting a dosage of a material in an animal.
In any one of the aforementioned embodiments of the present invention, the stainless steel comprises Fe and 0.01-3.0 wt % Si, less than 0.03 wt % P, 4-25 wt % Cr, 0.003-7.0 wt % Al, 0.01-1.0 Mn, 0.001-0.03 wt % S, 0.01-5.0 wt % Mo, 0.01-1.0 wt % Ti, 0.003-0.08 wt % C, 0.01-5.0 wt % Ni, 0.01-0.5 wt % Cu, less than 0.01 wt % Pb, 0.02-0.5 Bi, 0.5-1.0 wt % Nb, 0.02-1.0 wt % Zr, and 0.05-1.0 wt % V. Preferably, a stainless steel alloy comprising Fe and 0.36 wt % Si, 0.20 wt % P, 24.68 wt % Cr, 0.01 wt % Al, 0.90 wt % Mn, 0.009 wt % S, 1.80 wt % Mo, less than 0.01 wt % Ti, 0.08 wt % C, 4.98 wt % Ni, 0.10 wt % Cu, and less than 0.01 wt % Pb.
Therefore, it is an object of the present invention to provide a needle cannula that is more resistant to breakage during the process of injecting animal health products into an animal.
It is also an object of the present invention to provide a needle cannula comprising a stainless steel alloy that is magnetized to facilitate detection of the broken needle cannula in the flesh of the animal using the metal detectors that are commonly used in the meat processing industry.
These and other objects will become increasingly apparent with reference to the following descriptions and the drawings.